import java.util.HashMap;
import java.util.Map;

public class Test1 {
    public static void main(String[] args) {
        Map<Integer,Integer> hash = new HashMap<>() ;
        hash.put(1, 2);
        hash.put(2, 3);
        hash.put(4, 5);
        System.out.println(hash.getOrDefault(6 , -1));
    }
}
